Integrated metabolomics and lipidomics in obese vs lean groups. An integrative method, 2-way orthogonal partial least squares (O2PLS), was used to construct a metabolite-lipid correlation network using correlations between the 50 lipids and 50 metabolites with the highest loading values. These 50 metabolites and 50 lipids generated 2500 statistically significant correlations (adjusted P < .05), of which the top 100 correlations are represented in the correlation network, which contains 13 metabolites (blue circles) and 50 lipids (gray circles). Candidates from the most significant metabolite subpathways “gamma-glutamyl amino acid” (ie, gamma-glutamyl valine, gamma-glutamyl leucine) and “leucine, isoleucine and valine metabolism” (ie, leucine, 1-carboxyethylvaline) correlated to lipids from the most significant subpathways lipid pathway “TAG ester”.